PARSEC is a new stellar evolution code developed by the PAdova & TRieste Stellar Evolution Code team. It represents an updated version of the code used to compute stellar evolutionary tracks in Padova. The code has been revised to include new input physics, such as updated equations of state, opacities, and nuclear reaction rates, as well as the pre-main sequence phase. It also allows for the generation of accurate opacity tables consistent with any initial chemical composition by coupling the OPAL opacity data with the molecular opacities computed using the ESOPUS code. The code provides extended sets of stellar evolutionary models for various initial chemical compositions, including different metallicities and distributions of heavy elements. For the current release, the solar distribution of heavy elements from Caffau et al. (2011) is used, corresponding to a solar metallicity of Z ≈ 0.0152. From all computed stellar tracks, isochrones in several photometric systems are derived. The aim is to provide the community with the basic tools to model star clusters and galaxies using population synthesis techniques. The code includes detailed input physics, such as the solar distribution of heavy elements, opacities, and the equation of state. It also incorporates nuclear reaction rates, neutrino losses, and convection. The code accounts for overshooting in the convective core and envelope, as well as breathing pulses and semiconvection. The code also includes microscopic diffusion and is calibrated against solar data to ensure accuracy. The code is used to compute stellar evolutionary tracks for a range of initial masses from 0.1 M☉ to 12 M☉, covering the pre-main sequence phase up to the onset of thermally-pulsing AGB or carbon ignition. The code provides isochrones in several photometric systems, allowing for the modeling of star clusters and galaxies. The code has been tested against solar data and is calibrated to ensure accurate results. The code is also used to compute evolutionary tracks for different initial chemical compositions, including those with α-enhanced or α-depleted elements.PARSEC is a new stellar evolution code developed by the PAdova & TRieste Stellar Evolution Code team. It represents an updated version of the code used to compute stellar evolutionary tracks in Padova. The code has been revised to include new input physics, such as updated equations of state, opacities, and nuclear reaction rates, as well as the pre-main sequence phase. It also allows for the generation of accurate opacity tables consistent with any initial chemical composition by coupling the OPAL opacity data with the molecular opacities computed using the ESOPUS code. The code provides extended sets of stellar evolutionary models for various initial chemical compositions, including different metallicities and distributions of heavy elements. For the current release, the solar distribution of heavy elements from Caffau et al. (2011) is used, corresponding to a solar metallicity of Z ≈ 0.0152. From all computed stellar tracks, isochrones in several photometric systems are derived. The aim is to provide the community with the basic tools to model star clusters and galaxies using population synthesis techniques. The code includes detailed input physics, such as the solar distribution of heavy elements, opacities, and the equation of state. It also incorporates nuclear reaction rates, neutrino losses, and convection. The code accounts for overshooting in the convective core and envelope, as well as breathing pulses and semiconvection. The code also includes microscopic diffusion and is calibrated against solar data to ensure accuracy. The code is used to compute stellar evolutionary tracks for a range of initial masses from 0.1 M☉ to 12 M☉, covering the pre-main sequence phase up to the onset of thermally-pulsing AGB or carbon ignition. The code provides isochrones in several photometric systems, allowing for the modeling of star clusters and galaxies. The code has been tested against solar data and is calibrated to ensure accurate results. The code is also used to compute evolutionary tracks for different initial chemical compositions, including those with α-enhanced or α-depleted elements.